As described in the incorporated related applications, tape and reel supply of electrical parts for automatic pick-and-place by a mechanical or pneumatic device onto a PCB or similar device is well known in the art, but employed a series of pockets into each of which is placed a separately made electrical component. The assembly is then covered with a plastic strip and reeled up on a reel. During assembly of the PCB, the carrier tape is unreeled, the plastic strip removed, and a pick-and-place head is used to contact and pick a surface mount technology (SMT) component out of a carrier pocket and place it in a desired position, usually under control of a computer, on one or more tinned PCB pads.
The related applications described an improvement on this scheme by molding at least one continuous flexible film strip or filament to a side of each of a series of desired electrical or mechanical components such that the components are supported by the film strip or filament. The molded connection between each of the components and its supporting strip or filament is such that the components are ready separated from its supporting strip or filament in any one of several ways, such as by pushing, pulling or cutting, without damage to it or its neighboring components. Typically, the body of the electrical or mechanical component molded to the supporting strip or filament is of a moldable material, or at least has a part of moldable material that can be molded to the supporting strip or filament. Preferably, the body part of the electrical or mechanical component is molded to the supporting strip or filament by a semi-continuous injection molding process while a portion of the supporting strip or filament overlaps the mold cavities. The supporting strip or filament with the attached body parts can then be advanced to a fresh section and new body parts molded to it during a second molding cycle, and so on, to form a continuous strip of components supported on one or both sides by the continuous strip or filament.
Among the advantages of this scheme are a continuous strip of components that can be reeled up onto a reel for sale or distribution to a PCB assembler. The latter places the reel of molded parts onto a conventional feeding device which can use the sprocket holes or other equivalent structure on the supporting strip or filament for feeding the resultant carrier to, for example, an automatic pick-and-place machine. The parts can then be separated from the supporting strips, picked up by a conventional pick-and-place device in the machine and placed onto the PCB in the normal manner. A result is that the cost of fabricating packaged parts on a continuous carrier tape for automatic placement on PCBs is greatly reduced. In addition, the supporting strip or filament can be constituted of any material that can be attached to the moldable region of the component while the region is molded. The supporting strip or filament preferably is of a plastic that is different from the moldable region of the body. In addition, a die-casting process can be substituted for the plastic molding, since die-casting of low-melting point metals is in many ways similar to that of injection molding of plastics. The incorporated related applications also describe several ways of processing the resultant assembly following the molding step. In one embodiment, in the manufacture of pin headers, after the molding of plastic headers to the supporting strip or filament, the assembly is reeled up and supplied to a conventional insertion machine wherein metal pins can be inserted in pre-molded holes in the headers, and then the still-supported pin headers again reeled up for later sale or distribution. In another embodiment, after the molding step but before reeling up onto a reel pins can be inserted into the plastic bodies and caps placed over the pins to facilitate pick up by a pick-and-place device, and then the resultant product reeled up for later sale or distribution.